Credit card payoff calculator
How many months a card balance takes to clear at a fixed payment.
Fill in the fields and the result will appear here automatically.
Calculates duration and interest for one balance at a constant nominal annual rate with an equal payment at month-end. The term is the result of the balance, rate and payment rather than an input. If payment does not exceed monthly interest, the balance does not shrink and the tool reports that condition. The table separates payment, interest, principal repayment and closing balance; daily accrual, new purchases and fees are outside this model.
How it works
Formula and logic
Monthly rate r = annual percentage / 1200. With balance B and constant payment P, months for r > 0 are −ln(1 − B×r/P) / ln(1+r), rounded up; at zero interest, round B/P up. Interest accrues before each month-end payment, and the final payment is reduced to the amount due. If P ≤ B×r, the balance does not decrease in this model. Horizons above 600 months exceed its range; the table shows the first 36 months. Internal amounts are not rounded to cents.
Example
A 100,000 balance at 24% with a 5,000 payment clears in 26 months and costs 28,987.28 in interest.
Fields and units
- Card balance — $
- Annual rate, % — unitless
- Monthly payment — $
How to use
- — Enter the current balance on the card.
- — Give the annual rate from the terms — it also appears on the statement.
- — Set the amount you can pay every month.
- — Compare the first-month interest line with your payment: if they are close, the balance barely moves.
Method and limitations
- Calculation method
- Formula and logic
- Data or methodology source
- CFPB, United States: daily accrual and separate rates explain differences from a monthly model
- Limitation
- One balance, a constant nominal annual rate and month-end payments; no new purchases, fees, grace period or daily issuer accrual. Check the applicable rate and card terms in the contract.
FAQ
How is this different from paying off a loan?
A loan-payment tool normally takes a term and solves for payment. Here the balance, rate and payment determine the term. This is a difference between model inputs; check an actual card or loan contract separately.
Why does it refuse to answer at a small payment?
Because below the monthly interest the balance grows rather than falls. The formula would take a logarithm of a negative number — nonsense dressed up as an answer.
Is the interest-free period included?
The grace period and its eligibility conditions are not modeled. At 0% you can estimate interest-free repayment: a 30,000 balance with a 5,000 payment needs 6 months. Check actual grace conditions in the contract.
Why does the bank quote a different figure?
Banks accrue interest daily on the actual balance and add servicing and cash-withdrawal fees. This gives a monthly estimate without fees.